A DISPUTE has broken out among psychologists over whether listening to Mozart can improve mental ability.

Several studies have suggested that the Austrian composer's works, particularly his piano sonatas, have a pronounced effect on a person's cognitive prowess. However, two groups of psychologists have complained in the journal Nature that they have been unable to reproduce the results and it is time to give draw a veil over the "Mozart effect".

Frances Rauscher, a psychologist at the University of Wisconsin, reported six years ago that volunteers who listened to Mozart's Sonata for Two Pianos in D Major could do certain mental task with greater efficiency as a direct result of the music .

Christopher Chabris, a psychologist from Harvard University, said the "startling effect" attributed to Mozart has intrigued scientists because it appeared to demonstrate that exposure to the composer's music can raise IQ scores by as much as 10 per cent. However, Dr Chabris re- analysed 16 studies of the Mozart effect and found that their conclusions could not be supported.

"Exposure to 10 minutes of Mozart's music does not seem to enhance general intelligence or reasoning, although it may exert a small improving effect on the ability to transform visual images," he said. This enhancement is probably due to Mozart's music having a positive effect on a person's mood.

A separate team of researchers, led by Kenneth Steele of Appalachian State University in Boone, North Carolina, tried to repeat the Mozart experiments and likewise found "little evidence" for the effect.

Dr Rauscher, nevertheless, stands by her studies, saying that further, unpublished studies will support the Mozart effect. "Because some people cannot get bread to rise does not negate the existence of a `yeast effect'," she said.